import java.util.ArrayList;

public class E01_Gerbil {
	
	public static void main(String[] args) {
		ArrayList<Gerbil> gerbils = new ArrayList<Gerbil>();
		gerbils.add(new Gerbil());
		gerbils.add(new Gerbil());
		gerbils.add(new Gerbil());
		gerbils.add(new Gerbil());
		gerbils.add(new Gerbil());
		for (int i = 0; i < gerbils.size(); i++) {
			gerbils.get(i).hop();
		}
	}
}

class Gerbil {

	private static int counter = 0;;
	private final int gerbilNumber = counter++;

	public void hop() {
		System.out.println(gerbilNumber + " is jump");
	}

}